__I am updating to High Sierra macOS 10.13 right now – I did not hear about real problems – but will report them, so check back here to get more information. I will post them alongside my work with it.

a 2 TB SSD – gets me 5-6 GB more room, so it’s not really much you can save – not as much as on iOS 11. Another SSD (512GB) saved me 8GB, a bit more – on an older MBP it was 10-11GB. All attached SSD were not automatically converted to APFS. Note – APFS-SSDs won’t be recognized on any system lower than High Sierra – of course. I did not notice any free GB after converting external SSDs. It takes just a few seconds. No need to reformat. But maybe my second SSD needs to …

Motu AVB Interfaces, Ableton Live and Logic seem to work normally.

the main thing in this update is the new file system for SSDs: APFS (apple file system) – it will make more capacity available and it will be faster. non-flash memory will NOT work with APFS and stay at HFS+ – including Fusion Drives. it will be the last 32bit capable OS as well.